| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had been [det] | 529 |
|
| 2 | had been [to-vb] | 293 |
|
| 3 | had [det] [to-vb] | 253 |
|
| 4 | been [det] [to-vb] | 77 |
|
